Lack of timely follow-up of an abnormal mammogram result can lead to a delay in breast cancer diagnosis, and in turn a more advanced cancer. Moreover, delays in resolution (defining the abnormality as either cancer or benign) often cause psychological distress, including anxiety and depression. Multiple studies have found delays in resolution to be common, and more prevalent for minority than for white women. Under the Affordable Care Act more underserved women are expected to establish primary care and receive preventive services such as mammograms. With this influx of more vulnerable women into the healthcare system, it is important to understand what strategies contribute to timely follow-up specifically for this population. The overarching goal of this proposal is to inform the development of a system intervention to decrease disparities in timeliness of abnormal mammogram follow-up for vulnerable women. This proposal is based in the San Francisco Mammography Registry (SFMR), a registry of all women having mammograms at twelve participating radiology facilities in two Northern California counties. Our preliminary work has categorized SFMR facilities as having either timely or delayed follow-up. This proposal builds upon that work by testing candidate actionable systems-based communication and care coordination strategies with women and referring physicians. Our investigation encompasses the following specific aims: Aim 1. Test candidate areas for improvement from our radiology facility data utilizing interviews with vulnerable women about their experiences, and elicit additional experiences with communication and coordination of care after an abnormal mammogram result, perceived system facilitators and barriers to timely follow-up, and specific recommendations for system improvements to facilitate timely follow-up. Aim 2. To a) test candidate areas for improvement from our radiology facility and Aim 1 data, utilizing a survey of referring physicians about their experiences with follow-up of abnormal mammograms; and, in order to identify those specific factors with the most potential for intervention, investigate b) physician perceived acceptability and feasibility of the women's recommendations for system improvements and, c) the association of facility characteristics with physician report of facility performance on communication, access and care coordination.